John Deere 300 Industrial hydraulic problems

[Arob]

I recently started experencing the same problems you experenced on your 300. There is alot of great advise here. My question is the Owner of the 300. Did you get your Hydrolic problem fixed? If so what additional advise could you provide to a 1020 owner just beginning the diagnostics to the same hydrolic problems.
Thanks

 

[Arob]

didn;t see page two very helpful. thanks

 

[MAYTAG MAN]

This thread was EXTREMELY helpful...my JD 300 backhoe/loader is old (1972) with lots of problems like a transmission filter housing with a replacement bolt (full thread) and NO FILTER !!!! :laughing: I learned on another thread that water gets in the hyd system and causes excessive pressure in the filter housing that breaks the 5/8 bolt and blows the filter housing right off the tractor. NICE DESIGN, EH? Also learned on THIS thread the basic operation of the closed system, very nice and well stated. NOW I understand the way the system works!!! THANKS. One good thing, no metric bolts. :dance1::dance1::drink:

 

[GHOSTSS]

It appears this thread just keeps living on, so I guess it's my turn. I have a Jd300 Backhoe and am having a similar yet different problem from the others. The main issue is starting. I have had fits getting it started more than once a day. I know that sounds funny but when I found it and brought it home, it had been sitting for approx. 2 years. I put a hot battery on it and it fired up immediately. Once I shut it off it wouldn't restart. Barely turn over. Jumped it, same issue. I let it sit overnight and it fired first thing again. Everything worked perfect. Hydros etc. except for the occasional dead spell of the loader, then shaking, then working. Backhoe worked fine the whole time. Shut it off..... barely turned over and no restart.

I have cleaned all the wires and battery cables, put a 1000+ cranking amp red top ultima on it (new) and a new starter. Same issue. I have been reading all I can and the best theory I can come up with is that the hydros are holding back pressure and not allowing it to turn over. Could it be the stroke control valve in the pump or possibly another valve stuck? If I hold the lift lever for the loader or backhoe and turn it over, it doesn't slow it down any. Turns over just as slow either under load or not. Makes me think its always under load.
I also changed all the fluid and both filters but didn't know about the screen. I keep reading about it, but can't find it.

Any help would be appreciated. It appears to me that either the hydros are putting back pressure on the motor when I try to start it and after sitting a while, the pressure leaks off allowing it to spin over faster or I have a motor issue that only shows itself when its warm. Motor runs fine once it's going though.

Also I have no brakes and it is very slow to go into forward. I have the 8 speed with forward/reverse selector on the dash. Also the column gets very hot, I figure from the power steering.

Sorry to be all over the place, but maybe someone can point me in the right direction. I've worked on cars my whole life, but never messed with Hydros or a diesel for that matter. Is all new to me.

 

[J_J]

I believe the system is a closed center system, so the pump will be trying to pump up to a standby pressure at the git go.

If there is a valve lever engaged somewhere, there will be a load on the system.

All valves will have pressure at the IN port.

Check all valves for neutral position.

Are your 3pt arms down when you try to start?

Do they jump up to the raise position when you try to start?

Can you cut the BH out of the circuit?

Why not install a 3000 psi pressure gage and use it to monitor and troubleshoot the hyd system.


John Deere 300 http://www.tractordata.com/industrial-photos/F000/10/10-td3a.jpg


1965 - 1973
Industrial tractor

Hydraulics:
Type: closed center
Capacity: 10 gal [37.9 L]
Pressure: -unknown-
Valves: 1 or 2 optional
Total flow: 6.5 gpm [24.6 lpm]
13 gpm [49.2 lpm] (optional)
23.5 gpm [88.9 lpm] (optional

 

[GHOSTSS]

It doesn't have 3 point arms. Just the backhoe on the rear. All valves are at neutral. Only thing that moves when I try to start it is the steering wheel jumps around. I wonder if the power steering could be pulling a load?

 

[J_J]

If you knew the stand by pressure, and a gage installed, then you could see if there was a load on the hyd system.

 

[medic0648]

My 301a does the same thing. I have to work all the hyd functions and hold the loader valve open to remove enough pressure to start. The screen should be just to the rear of the hyd filter under the tractor. There is also a little screen in the pump maybe 3/4" in diameter.

 

[Tx Jim]

Easiest thing to do to aid starting is install a de-stroking screw in hyd pump and use it when cranking engine or rapidly move steering wheel back-n-forth while cranking. The DS screw cost about $15. Which size hyd pump does your tractor have and does pump have a serial number plate?

 

[GHOSTSS]

I haven't torn into it yet to see. Where would I look for the serial plate or model on the pump?